Ignition apparatus



Dec. 3, 1946. w. J. SPE NGLER 2,412,102

IGNITION APPARATUS Filed June 12, 1943 27 32 7 30 46 27' 4 a as I, g; 4,FIG. 4

IN V EN TOR. [1/

2 I I ATTORNEY Patented Dec. 3, 1946 UNITED STATES PATENT OFFICEIGNITION APPARATUS Application June 12, 1943, Serial No. 490,667

and more particularly to means for transforming voltages for firing thespark plugs in an ignition system of an internal combustion engine.

One of the objects of the present invention is to provide a novel andadvantageous means for a simplified arrangement of a plurality oftransformer coils in an ignition system wherein the current isdistributed at primary or generated voltage and stepped up at coilsmounted near the spark plugs.

A further object is to provide a structure embodying a novel arrangementof the above character which is sturdy and reliable and whereby asubstantial saving of space and weight is realized without sacrificingany advantages of structures heretofore provided for the same purpose.

Another object is to provide apparatus of the above character wherebythe radio-shielding required for the entire ignition system is reducedto a minimum, thereby materially reducing the possibility of failures.

Still another object is to provide apparatus of the above characterwhich is so constructed that the operation thereof will not be afiectedby rarefied atmosphere and low pressures at high altitudes.

The above and further objects and novel features of the invention willmore fully appear from the following detailed description when the sameis read in connection with the accompanying drawing. It is to beexpressly understood, however, that the drawing is for th purpose ofillustration only and is not intended to define the limits of theinvention, reference for this latter purpose being primarily had to theappended claims.

In the drawing, wherein like reference characters refer to like partsthroughout the several views,

Fig. 1 is a side elevation view mostly in section and with parts brokenaway showing one form of structure embodying the features of the presentinvention, the section being taken substantially on line l--| of Fig. 2;

Fig. 2 is a top plan view of the structure shown in, Fig. 1 with thecover and filling material removed;

Fig. 3 is a detail plan view, partly in section, showing the main casingof the structure of Fig. 2; and,

Fig. 4 is a detail sectional view with parts 12 Claims. (01. 175361)i;... This invention relates to electrical apparatus 2 broken away, thesection being taken substantially on line 4-4 of Fig. 2.

A single embodiment of the present invention is illustrated in theaccompanying drawing, by way of example, in the form of a nest of fourtransformer coils [0, which is particularly adapted for use on a doublerow radial engine having dual ignition, As illustrated, each of the fourcoils are identical, and hence interchangeable, thereby minimizingmanufacturing and installation costs and problems and facilitatingreplacements when necessary. Each of said coils consists of the usualprimary and secondary windings wound on a metallic core ll, saidwindings being enclosed in a cylindrical casing [2 of insulatingmaterial. Each of the cores H consists of a plurality of rectangularlaminations, each having an arm 13 extending through the coil, a similararm l4 extending parallel to arm 13 at the periphery of the coil and tworadially extending arms I5 and i6 at the ends of the coils connectingthe ends of arms 13 and I4.

Coils ID with their input and output terminals, to be hereafterdescribed. are preferably enclosed and, hence, radio-shielded by atwo-part metallic housing consisting of a substantially cylindrical maincasing member H and a cover l8. The closed end or bottom IQ of easingmember Il'is provided on its inner face with a groove or recess 20 inthe form of a cross (Fig. 3) for receiving th positioning arms of'thecoil cores, said cores being arranged'with the exposed arms I4 thereofadjacent one another at the center of easing I1. 7

At any convenient position at the closed end 59 of easing member [1. anopening 2| is provided for incoming conductors from a source of currentwhich feeds the primary windings of coils iii. A multiple socket 22 of aplug and socket connection, which may be of any suitable type, such asthose known as Cannon plugs, is mounted in opening 2! and each of thesocket conductors 23 is connected by an insulated lead M to the primarywinding of a coil l0. As seen in Fig. l, the thickness ofcore arms I5 isgreater than the depth of recess 2!] by a sufficient amount to permitconductors 24 to pass between bottom closure is and the lower ends ofcoils IS. The plug of the detachable connector may be removably held inplace by a nut which engages the threaded portion 25 of socket 22 in amanner well understood in the art.

Cover I 8 is preferably provided with a depending annular flange 26which closely surrounds the upper edge of easing [1. Any suitable means,

such as screws 21, may be provided for securing the cover to casingmember If. Screws 2'! may engage threaded openings 28 tapped into bosses29 on the interior of said casing member (Fig. 2). The inner face ofcover I8 is provided with a groove 30 similar to and. directly oppositegroove .20 for receiving and positioning arms I6 of coil cores II. Thecore and coil assemblies Ifl, II are thus firmly held in predeterminedpositions in casing I'I, I8. If desired, a spacer 3I of wood or othersuitable material may be inserted between arms Id of coil cores II atthe center of casing member II. Cover I8 is also provided with foursymmetrically-spaced,

inafter, said nipples being disposed directly above and concentric withfour circular recesses 33 in bottom I9 of easing member [1.

Before cover I8 is placed in position, suitable sockets with terminalsconnected to the output ends of the secondary windings 34 of coils Illand adapted to receive detachable plug connectors are installed incasing member I! and the connected ends of the primary and secondarywindings of each coil are connected to ground by means of insulatedleads 35 which are conductively attached to casing I! by any suitablemeans, such as screws 36. Each of the sockets for a high tension oroutput terminal comprises a rigid insulating tube 37, the upper end ofwhich has a close sliding fit in a nipple 32 of cover IS. The lower endof each tube 31 rests upon a block 38 of suitable insulating material,which is, in turn, positioned in the bottom of casing member I 1' by arecess 33 or held in place by means of glue or the like for assemblypurposes.

Resting on an internal shoulder 39 intermediate the ends of tube 31 is afabricated terminal 40 which comprises a washer or plate M engaging saidshoulder and a depending coil spring 42. The lower hooked end 43 of saidspring operatively engages a rigid metallic bracket 44, which is securedto the wall of coil casing I2 (Fig. 4) and is electrically connected tothe high voltage en'd'of secondary Winding 34 of the coil. The laterallyextending portion of bracket 44 to which spring 42 is hooked extendsthrough a groove or slot 45 in the'lower end of socket tube 3'! and,hence, serves to limit the angular movement of the tube about itslongitudinal axis. Since spring 42 is extensible and retractable, thesame materially facilitates the assembly of the coils and sockets andinsures against the possibility of fiashovers in the assembled unit bykeeping the high tension conductors Within tube 3! insofar as ispossible and, hence, a maximum distance from any grounded metal parts.

A spring 46 may be connected to terminal '50 for making contact with aconnector plug (not shown) adapted to be received by socket tube 3'! andto be detachably secured to nipple 32 by means of a nut 41 in a mannerwell understood in the art. A shielded lead 48 from the connector' plugmay extend to a spark plug in an engine or other point of use for thehigh tension current from secondary winding 34.

For the purpose of providing further assurance against flashovers fromthe high tension conductors and terminals to the other metallic parts ofthe structure and of obviating the bad effects of changes in pressuresresulting from changes in altitude, the entire space around coils I andsockets 31 within casing I'I, I8 is preferably filled with an insulatingcompound. Polymers of cashew-nut-shell oil or linseed Oil haveexternallythreaded nipples 32 for a purpose to appear here-- been foundsatisfactory for this purpose. The

filling material is preferably injected with the aid of vacuum orpressure while in the form of a viscous liquid. A suitably drying orsetting agent, such as paraformaldehyde or the like,

may be mixed with the liquid polymers to facilitate setting thereofthroughout without th aid of oxygen. Heat may be applied to facilitatethe setting action. It is preferable that the filling material used beof such a nature that it will set to a yieldable but non-moldable solidform which will permit removal of the coils and filling material fromthe casing without damage to the coils when disassembly of the unit isnecessitated. During the filling operation, socket tubes 3'! aboveterminals 59 may be substantially filled with a suitable plug. toprevent the compound from filling the well which is intended for theconnector plug. Many types of suitable connector plugs are well-known inthe art and in common use today. The fillin material may be injectedthrough a filling hole 49 while air or other gases are permitted toescape through a bleed port 58.

To further provide against the possibility of fiashovers within casingIi, IS, a piece of varnished cambric M or like insulating material maybe passed between each coil and arm I4 of the core thereof and extendbetween the terminal socket 3! attached to said coil and the casing ofan adjacent coil (Fig. 2). This provides insurance against fiashoversfrom the high tension terminals and particularly brackets 44 to thecores II of the coils.

Casing member I! is preferably provided with an external flange 52which, together with the extending portion 26 of cover I8, forms anexternal channel to receive suitable means for mounting the coil unit onan engine. The mounting means preferably comprise some suitableyieldable material so that all the vibrations and shocks of the enginewill not be transmitted to the coil unit. The novel coil unit disclosedis particularly adapted to be mounted between two adjacent cylinders inthe front row of a double 45 row radial engine so that it may serve fourspark plugs located near it, such as the spark plugs in one rear rowcylinder and one front row cylinder of a double row, radial engine.

Only a relatively short shielded lead 48 between 50 each of theterminals 48 and a spark plug of the engine is thus required. The fourinput leads entering socket 22 from a suitable distributor may beshielded in a single conduit which may, in turn, extend from a shielding55 harness manifold of any suitable type well-known in the art.

There is thus provided a novel structure whereby a plurality of ignitioncoils adapted for use in a low tension ignition distribution system 60may be simply and compactly arranged in a substantially air-tight casingand yet provide ample protection against fiashovers and ampleradioshielding. Additionally, the coil unit provided is sturdy andreliable in use and may be con- 65 veniently and advantageously mountedon the engine. The readily detachable electrical connections make itpossible to renew the leads which deteriorate in use more readily thanmost other parts of an ignition system. The detachable 7 leads alsofacilitate assembly and installation.

Although only a single embodiment of the invention is illustrated anddescribed, it is to be expressly understood that the same is not limitedthereto. For example, the number and arrange- 5 merit of the coils maybe varied, such as by plac ing the same in a single line in an oblongcasing. Various other changes, particularly in the arrangement anddesign of the parts illustrated, may be made without departing from thespirit and scope of the invention, as will now be apparent to thoseskilled in the art. For a definition of the limits of the invention,reference is had primarily to the appended claims.

What is claimed is: V

1. In apparatus of the class described, a metallic casing comprising abody portion and a cover removably secured thereto, said cover having aplurality of outlets therein, a plurality of ignition coils in saidcasing, each having primary and secondary windings, a metallic core foreach of said coils forming a magnetic flux path around a portion of thelatter, opposed recesses in said body portion and cover for receivingportions of said cores to position said coils in said casing, aninsulating tube adjacent each coil, each of said tubes slidablyextending into one of said outlets in the cover, a terminal in each ofsaid tubes, means connecting each of said terminals to the highpotential end of the secondary winding of an adjacent coil, a socket ofa multiple plug and socket connector in said body portion, meansconnecting the terminals of said socket to the ungrounded ends of theprimary windings of said coils, and means connecting the adjacent endsof the primary and secondary windings of each coil to the casinginteriorly thereof for grounding the same.

2. In apparatus of the class described, a metallic casing comprising abody portion and a cover removably secured thereto, said cover having aplurality of tubular outlets therein, a plurality of ignition coils insaid casing, each having primary and secondary windings, a metallic corefor each of said coils forming a magnetic flux path around a portion ofthe latter, said body portion and cover having opposed internal recessesfor receiving portions of said cores to position said coils in saidcasing, an insulating tube adjacent each coil, each of said tubesslidably extending into one of said outlets, a terminal in each of saidtubes, means including an extensible resilient conductor under tensionconnecting each of said terminals to the high potential end of thesecondary winding of an adjacent coil, a socket of a multiple plug andsocket connector in said body portion, means connecting the terminals ofsaid socket to the ungrounded ends of the primary windings of saidcoils, means connecting the adjacent ends of the primary and secondarywindings of each coil to the casing interiorly thereof for grounding thesame, and a filler of yieldable solid insulating material in a drynon-moldable state filling the space in said casing around said coilsand tubes and filling said tubes around said terminal connecting means.

3. In apparatus of the class described, a metallic casing comprising asubstantially cup-like body and a cover removably secured to the openend of said body, oppositely facing internal recesses in the bottom ofsaid body and said cover, said casing being filled with insulatingmaterial and containing a plurality of transformer coils having primaryand secondary windings, a metallic core for each of said coils, each ofsaid cores comprising a pair of spaced arms extending longitudinally ofthe coil, one of said arms extending through the central opening in saidcoil, and a pair of arms extending between the adjacent ends of saidfirst-named arms, said second-named pair of arms extending into saidrecesses to position said coils in said casing, an elongated socketextending longitudinally of each coil and communicating with theexterior of said casing, and a terminal in each of said socketsconnected with the secondary winding of an adjacent coil.

4. In apparatus of the class described, a metallic casing comprising asubstantially cup-like body and a cover removably secured to the openend of said body, oppositely facing internal recesses in the bottom ofsaid body and said cover, a plurality of transformer coils havingprimary and secondary windings, and a metallic core for each of saidcoils, each of said cores comprising a pair of spaced arms extendinglongitudinally of the coil, one of said arms extending through thecentral opening in said coil and a pair of arms extending'between theadjacent ends of said first-named arms, said second-named pair of armsextending into said recesses to position said coils in said casing, saidcoils being arranged in the casing with the external longitudinallyextending arms of said cores adjacent the center of the casing and withthe coils and their connec- \tiOllS set in solidified insulation.

5. Inapparatus of the class described, a metallic casing comprising asubstantially cup-like body and a cover removably secured to the openend of said body, said cover having a plurality of outlets therein,oppositely facing internal recesses in the bottom of said body and saidcover, a plurality of transformer coils having primary and secondarywindings, a metallic core for each of said coils, each of said corescomprising a pair of spaced arms extending longitudinally of the coil,one of said arms extending through the center opening in said coil and apair of arms extending between the adjacent ends of said first-namedarms, said second-named pair of arms extending into said recesses toposition said coils in said casing, an elongated insulating tubeadjacent each coil having the upper end thereof slidably extending intoone of said outlets, a terminal in each of said tubes, and meansincluding an extensible resilient conductor for detachably connectingeach of said terminals to the secondary winding of an adjacent coil.

6. In apparatus of the class described, a metallic casing comprising abody portion and a cover removably secured thereto, a plurality ofignition coils in said casing, each of said coils having a primarywinding, and a secondary winding and terminals connected therewith, anda closed 3 metallic core for each of said coils forming a magnetic fluxpath around a portion of the latter,

said body portion and cover having opposed in-' ternal recesses intowhich radially extending p01 'tions of said cores at opposite ends ofsaid coils fit for positioning said coils in said casing, and saidcasing being filled with insulating material whereby the coil and itsconnections are protected against shock and insulated againstflashovers.

'7. In apparatus of the class described, an insulation-filled, metalliccasing comprising a body portion and a cover removably secured thereto,said cover having a plurality of outlets therein withinsulation-retaining means separating their outer from their innerportions, a plurality of ignition coils in said casing, each of saidcoils having a primary winding and a secondary winding, a closedmetallic core forming a magnetic flux path around a portion of each ofsaid coils, said body portion and cover having opposed recesses into.which radially extending portions ofsaid cores at opposite ends of saidcoils, fit for positioning said coils in said casing, said coils beingarranged, with the longitudinally extending portions of the coresoutside said coils adjacent the; center of the casing, and an elongatedinsulating socket communicating with each of said outlets and extendinglongitudinally of said coils, and a terminal in each of said socketsconnected with they secondary winding of an adjacent coil.

8. In apparatus of the class described, a twopart metallic casing, atleast one of said parts havingla plurality of outlets therein, means forremovably securing said parts together to form a closed casing, aplurality of ignition coils in said casing, each of said coils having aprimary Winding; and asecondary winding, a substantially closed metalliccore for each of said coils forming a magnetic flux path around aportion of the latter, said casing parts having opposed internalrecesses therein into which radially extending portions of said cores atopposite ends of the coils fit for positioning said coils in the eachcoil, a portion of each of tubes slidably extending into one of saidoutlets, a terminal in each of said tubes intermediate the ends thereofwhereby said tubes serve as sockets for removable plug connectors, andmeans for connecting each of said terminals to the high potential end ofthe secondary winding of an adjacent coil.

9. In apparatus of the class described, a twopart metalliccasing, atleast one of said parts having a plurality of outlets therein, means forremovably securing said parts together to form a closed casing, aplurality of ignition coils in said casing, each of said coils having aprimary winding and a secondary Winding, a substantially closed metalliccore for each of said coils forming a magnetic flux path around aportion of the latter, said casing parts having opposed internalrecesses therein into which radially extending portions of said cores atopposite ends of the coils fit forpositioning said coils in the casing,a tube of insulating material adjacent each coil, a portion of each ofsaid tubes slidably extending into one of said outlets, a terminal ineach of said tubes intermediate the ends thereof whereby said tubesserve as sockets for removable plug connectors, means for connectingeach of said terminals to the high potential end of the secondarywinding of an adjacent coil, a unitary plug and socket connector forconnecting the primary windings of said coils to a source of electricalenergy, and means connecting the adjacent ends of the primary andsecondary windings of each coil to the casing for grounding the same,

10. In apparatus of the class described, a twopart metallic casing, atleast one of said parts having a plurality of outlets therein, means forremovably securing said parts together to form a closed casing, aplurality of ignition coils in said casing, each of said coils having aprimary winding and a secondary winding, a substantially closed metalliccore for each of said coils forming a magnetic flux path around aportion of the latter, said casing parts having opposed internalrecesses, therein into which radially extending portions of said coresatopposite ends of the coils fit for positioning said coils in the casing,a tube of insulating material adjacent each coil, a portion oi each ofsaid tubes slidably extending into one of said outlets, a terminal ineach of said tubes intermediate the ends thereof whereby said, tubesserve as sockets for removable plug connectors, means for connectingeach of said terminals to the high potential end of the second- ,arywinding of an adjacent coil, and a yieldable solid insulating materialin a dry, non-moldable state filling the space in said casing aroundsaid coils and tubes and filling said tubes around said terminalconnecting means.

11. In apparatus of the class described, a metallic casing comprising asubstantially cup- =like body and a cover removably secured to the openend of said body, said cover having a plurality of outlets therein,oppositely facing crossshaped recesses in the bottom of said body andsaid cover, a plurality of transformer coils having primary andsecondary windings, a metallic core for each of said coils, each of saidcores comprising a pair of spaced arms extending longitudinally of thecoil, one of said arms eX- tending through the central opening in saidcoil, and a pair of arms extending between the adjacent ends of saidfirst-named arms, said second-named pair of arms extending into saidrecesses to position said coils in said casing, an elongated insulatingtube adjacent each coil having the upper end thereof slidably extendinginto oneof said outlets, a terminal in each of said tubes, meansincluding an extensible conductor for removably connecting each terminalto the secondary winding of an adjacent coil, and yield- ,able solidinsulation in a dry, non-moldable state surrounding said coils and tubesin said casing.

12. In apparatus of the class described, a metallic casing comprising asubstantially cuplike body and a cover removably secured to the open endof said body, said cover having a plurality of outlets therein,oppositely facing crossshaped recesses in the bottom of said body andsaid cover, a plurality of transformer coils having primary andsecondary windings, a metallic core for each of said coils, each of saidcores comprising a pair of spaced arms extending longitudinally of thecoil, one of said arms extending through the central opening in saidcoil, a pair of arms extending between the adjacent ends of saidfirst-named arms, said secondnamed pair of arms extending into saidrecesses to position said coils in said casing, an elongated insulatingtube adjacent each coil having the upper end thereof slidably extendinginto one of said outlets, a terminal in each of said tubes, meansincluding an extensible conductor for detachably connecting eachterminal to the secondary winding of an adjacent coil, yieldable solidinsulation in a dry non-moldable state surrounding said coils and tubesin said casing, and a thin sheet of insulating material, such asvarnished cambric, extending between each coil and the longitudinallyextending external core arm of the core therefor and between theterminal tube for said coil and an adjacent coil.

WALTER J. SPENGLER.

